Carburetor



Dec. 28 1926.

K.A.T.JOHANSSON CARBURETOR Filed April 10. 1922' 4 nl A5 Mw,

WAM f ATT NZC Patented STATES KARL A. EOHANESSGE, GF

CARBRETOR.

Application. filed, April l0, 1922.

This invention relates to improven'ients in carburetors and has tor its principal obiect the pr vision of a carburetor whereby the proportionate mixture ot air and hydrocarbon vapor will be maintained substantiallyv constant at varying' speeds ot the engine.

A further object ot my invention is to provide a simple and effective means ot creating a subatmospheric pressure in the fuel reservoir with automatic controllingv means to limit the ei-rtent of the drop in pressure.

The above and other objects ot my invention will be apparent trom the following description wherein reference is made to the accompanying' drawing` illustrating a preferred embodiment ot my invention, and wherein similar reference numerals designate .similar part-s throughout the several views.

' In the drawings Fig. 1 shows a side elevation ot an engine with my improved carburetor in position thereon;

FleQ is an enlarged central sectional 25 view through the carburetor, and

Fig. 3 is a detail sectionl through the aspirating iet and associated parts, taken substantially on the line 3-3 ot Fig. 2.

Referring now to the drawing the numeral 50 5 designates an internal combustion engine ot any desired construction having an intake manifold 6 leadingr trom the supply tube 7 of the carburetor 8 to the severa cylinders ot the engine. rlhe carburetor 8 is preferably secured to the lower extremity ot the intake manifold by bolts 9V passingv through apertured flanges 1() on the car buretor and manifold respectively.

The carburetor 8 is preferably constructed with a constant level fuel-chamber 11 havino; an intake opening 12 in its lower wall adapted to be connected with the pipe line 13 leading to a tuel tanl: (not shown). A needle valve 141 is adapted to close the inlet opening 12 when the fuel in the chamber 11 has reached the desired height, the valve 11ibeing controlled by a float 15 and levers 16 pivoted intermediate their ends upon the upper wall ot the fuel-chamber, substantially as shown in llifr. 2. One arm ot each lever 1G is engaged by the float 15 while the other arm ot each lever engages a collar 1'? on the needle valve lll, whereby the upward movement of the float incident to a rise in the level ot the liquid in the fuel-chamber will serve to torce the needle valve 11i down- Selial Elo. 559,350.

wardly to close the inlet opening 12. rl"he fuel-chamber 11 is connected, as by the passage 18, with the central bore 19 ot the piraffingiet 20, best shown in 3. The jet 2O is preferably so located relatively to the fuel-chamber that the liquid in the a:- pirating liet and tuel-chamlgier is normally at the height indicated by the dotted line in Fig. 2, with the liquid almost filling the bore 1.9 ot the jet. The air adapted 'to be mixed with the fuel carried in the jet 2O is adapted to ent r at the air-intake pipe. 21 and passes around the upper extremity ot the et V2O into the mixture-.supply pipe 'l' ot' P the carburetor. a Venturi tube action being secured by reducing the area ot the lower ei;- 'tremity ot the mixture-supply pipe .7 cent the top ot the iet 2O and then gradually. widening the area of the mixture-supplj.Y pipe above the jet 20. To adjust the eltective area ol the air-intake pipe 21 and the mixture-supply pipe l preferably con-A struct'the inclined lower portion ot the sup ply pipe '7y in a rotatable member 22 pivotally mounted in the side walls of the carburetor on pivots arranged in a planeslightly below the upper terminal ot the jet 20. A lever arm 23 is lined upon the projecting` end ot one ot the pivots ot thermember and connects with a rod 24 leading to the throttle-control lever on the steering wheel or to some other location convenient to the driver ot the automobile or other vehicle usine; the engine 5. The lower portion ot the rotatable member 22 is hollowed out to form an air passage 22a normally forming' a continuation of the air-intake pipe 21, and the solid portion of the member 22 is ranged substantiall as shown in Fig. 2 so that upon rotation the solid portion ot the member 22 will swing across and so reduce the effective area ot the air-intake pipe 2l simultaneously with the reduction ot the ettective area ot the mixture-supply pipe 7. By virtue ot this construction l am able to contr l the admission ot air to the carburetor' so that mixture will be supplied to the engine cylinders suthiciently rich in fuel to start the engine and maintain it running' at any desired speed.

To regulate the supply ot tuel into the j et 20 at varying speeds ot the engine, I provide means tor producing` a sub-atmospheric pressure in the fuel-chamber 11 above the surface oi' the liquid therein, a passage 25 leading trom the upper portion ot the fuel-chamber 1l to the bore of a tube 26 preferably surrounding the jet 20, substantially as shown in Fig. 3. t its upper extremity the tube Q6 is inclined to receive a cap 27 having arranged at one side thereof one or more horizontally extending openings 28 leading to the bore ot the tube 26, and in the opposite side thereot, one or more inclined apertures 29 leading upwardly into the bore of the tube 26 (see Fig. 3). With this construction the air drawn by the upper terminal ot' the aspirating jet 2O by the suction of the engine, lvill produce an entraining ettect tending to exhaust the air in the upper portion ot the fuel-chamber ll through the bore of the tube 26 and passageway 25, the air being drawn out through the horizontal openings 28. The inclined openings are so located to prevent an excessive exhaustii'in of the air in the fuel-chamber 1l because oit their arrangement in the path of the air entering through the air-intake pipe 2l, the in-rushing air passing through the inclined openings 29 to assist in breaking the partial vacuum in the tube 26. The area of the inclined openings 29 and the horizontal openings 28 may be so regulated as to produce reduction ot atmospheric pressure in the fuel-chamber 1l corresponding to the amount of fuel mixture needed by the cylinders of the engine 5 at varying speeds, the resultantmixture maintainingl a substantially constant proportion ot air and 'fuel regardless or' the speed of the engine.

As herein shown the aspirating jet 2O is provided adjacent its lower extremity with a flange 30 adapted to rest upon the lower wall of the opening 3l in the bottom wall of the carburetor, into which opening the stated, it is to be understood that the invention is susceptible to variation, modification and change within the spirit and scope ot the subjoined claim.

Having described. my invention, I claim The combination with a carburetor hav-V ing a constant level fuel-chamber and an intake passage, or' an aspirating nozzle eX- tending into the intake passage and connected with the fuel-chamber, means for producing a sub-atmospheric pressure in the fuel-chamber above the liquid therein, comprl a tube surrounding the nozzle and connected by an air passage with the upper portion ot the tuel-chamber, the tube having a series ot openings adjacent its upper extremity arranged so that the passage oitI the 'tuel mixture through the intake passage will exhaust the air from the tube, andthe tube having a second series of openings ot lesser area than the irst-mentioned series arranged to admit fuel mixture into the tube to restrict the extent of depression of such sub-atmospheric pressure.

n witness whereof hereunto set my hand.

KARL A. T. JOHANSSON. 

